1. Field of the Invention
The present invention relates to a contaminated fluid recovery apparatus for decontaminating a contaminated fluid containing, for example, chips and fine sludge.
2. Description of the Related Art
A machine tool for machining, such as cutting, grinding, etc., uses a fluid such as a coolant for cooling a workpiece. This fluid contains foreign matter, such as chips produced by machining, fine sludge, etc. A contaminated fluid recovery apparatus is used to reuse the contaminated fluid that contains the chips, sludge, etc. The contaminated fluid recovery apparatus removes the chips, sludge, etc., from the contaminated fluid.
The inventors hereof have long been investigating and developing contaminated fluid recovery apparatuses. In consequence, they have succeeded in developing a high-performance contaminated fluid recovery apparatus that combines a conveyor and a filter provided with a magnet drum, as described in, for example, Jpn. Pat. Appln. KOKAI Publication No. 2005-66820. This contaminated fluid recovery apparatus includes the magnet drum that is located at an overflow section near the liquid surface of a dirty tank. Fine magnetic sludge in a contaminated fluid is attracted to the outer peripheral surface of the magnet drum. The conveyor is provided with a plurality of scrapers. The scrapers scrape out relatively large chips and the like settled at the bottom of the dirty tank toward an exit section outside the dirty tank.
The contaminated fluid recovery apparatus is located so that a rotating shaft (axis) of a filter drum member is parallel to the direction of travel of the conveyor. Therefore, it requires two types of drive systems, a mechanism for driving the conveyor and a mechanism for rotating the filter drum. Thus, there is a problem that the drive systems are complicated and the contaminated fluid recovery apparatus becomes larger.
In the conventional contaminated fluid recovery apparatus, moreover, the filter drum member is located parallel to the direction of travel of the conveyor. Thus, an inlet port of the drum-shaped filter unit has a shape transversely elongated in the direction of travel of the conveyor. A contaminated fluid supply port through which the contaminated fluid to be decontaminated is fed into the dirty tank is disposed over the dirty tank.
If the inlet port is transversely elongated in the direction of travel of the conveyor, one end of the inlet port is situated nearer to the contaminated fluid supply port than the other end in a case where a sufficient space cannot be secured in the direction of travel of the conveyor. Thus, relatively large chips that are fed into the dirty tank through the contaminated fluid supply port get into the inlet port, thereby increasing the load on the filter drum member.